Effect of phase transformation and indium addition on workhardening characteristics of Al-Zn alloy

Tensile characteristics of both Al–10Zn and Al–10Zn–0·2In (wt-%) alloys were investigated in the temperature range from 413 to 473 K. The workhardening coefficient, the yield stress, the fracture stress, resilience, toughness and fracture time generally decrease with increasing deformation temperature. On the other hand, the fracture strain and dislocation slip distance increased with increasing deformation temperature. The two observed temperature regions around the transformation temperature (443 K), which characterise the magnitude of variation of these parameters point to two fracture mechanisms activated with 23·2 and 49·4 kJ mol−1 for the low and high temperature regions respectively. Indium addition caused general increase for all the measured strength parameters. The microstructures of the samples under investigation have been examined after stress–strain deformation by X-ray diffraction analysis.